Replacement eraser for use on lead pencils



Aug. 1.l-, 1970 c. B. FRANCIS REPLACEMENT ERASER FOR USE ON LEAD PENGILS Filed Aug. 28, 1968 I N VENTOR.

Charles B. Fran cls M6? MM ATTORNEY United States Patent Office 3,523,321 Patented Aug. 11, 1970 3,523,321 REPLACEMENT ERASER FOR USE ON LEAD PENCILS Charles B. Francis, 1833 13th Ave., Apt. 206, Seattle, Wash. 98102 Filed Aug. 28, 1968, Ser. No. 756,018 Int. Cl. B43k 29/02 US. Cl. 15-431 7 Claims ABSTRACT OF THE DISCLOSURE An eraser member of about the same size and shape as the usable part of an ordinary lead pencil eraser is attached to one side of a small mounting disc and an anchor member is rigid with and protrudes from the other side of the mounting disc and is adapted to be embedded in the stub of a worndown eraser on the pencil to firmly secure the replacement eraser close to and in line with the worndown eraser stub.

BACKGROUND OF THE INVENTION Field of the invention My invention relates to a replacement eraser for a lead pencil having a conventional eraser which has been worn down to a substantially non-usable condition.

Description of the prior art Ordinary lead pencils usually have rubber erasers of about the same diameter as the pencil attached to the non-pointed end of the pencil by a metal ferrule. These erasers often become worn down to such an extent that they are approximately flush with the end of the ferrule and non-usable long before the pencil is worn out. Erasers which can be applied to pencils by slipping them over the ferrules and worndown erasers on the ends of the pencils are available but these erasers are considerably larger in diameter than the usual pencil and for this reason are objectionably bulky when used on pencils carried in the pocket and most of them are heavy enough so they will adversely alfect the balance of fairly long pencils when used thereon.

SUMMARY OF THE INVENTION The principal objects of my invention are to provide a replacement eraser which is simple, inexpensive, easy to apply to a pencil with a badly worndown eraser and one which is small and compact enough so it is not objectionable due to bulkiness when used on a pencil which is carried in the pocket and is not heavy enough to adversely affect the balance of longer pencils to which it is applied.

Another object is to provide a replacement eraser comprising a small mounting disc of thin strong material having a rubber eraser of about the same size and shape BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in elevation, on an enlarged scale, of a replacement eraser constructed in accordance with my invention.

FIG. 2 is an end view of the same looking in the direction indicated by broken line 22 of FIG. 1.

FIG. 3 is a view partly in section and partly in elevation showing this replacement eraser applied to a lead pencil, a fragment only of the pencil being shown.

FIG. 4 is a side elevational view showing a modified form of my invention.

FIG. 5 is a side elevational view showing another modified form of the invention.

FIG. 6 is a side elevational view showing a third modified form of the invention.

Like reference numerals refer to like parts throughout the several views.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiment of my invention shown in FIGS. 1, 2 and 3 comprises a rubber eraser member 10 preferably of about the same size and shape as the usable part of an ordinary lead pencil eraser. The eraser member 10 has at least one flat end which is cemented or otherwise permanently attached to a small disc-shaped mounting member 11 of relatively stiff strong material, such as metal or plastic. The mounting member 11 has a rigidly connected anchor member 12 protruding from the side thereof opposite the eraser member 10. The anchor member 12 is of small diameter and is helically shaped like a cork screw and terminates in a pointed outer end. It can be treaded into a stub or base part 13 of a worndown eraser in a ferrule 14 on an end of an ordinary lead pencil 15 to firmly attach this replacement eraser to the pencil with the eraser member 10 close to and in alignment with the pencil and in substantially the position occupied originally by the worn away part of the pencil eraser.

Preferably one or more short tabs or lugs 16 are provided on the periphery of the mounting disc 11. These outwardly protruding lugs or tabs 16 prevent the pencil from rolling on a flat surface and are effective even though the fiat surface is slightly inclined relative to the horizontal. Also they tend to prevent the pencil from falling or being thrown out of the pocket. Also they serve as protruding parts with which the fingers can engage when the user is screwing the anchor member 13 into an eraser stub 14.

In the modified form of invention shown in FIG. 4 the eraser member 10 and disc 11 are the same as those shown in FIGS. 1 to 3. A straight anchor member 17 is rigid with said disc 11 and protrudes perpendicularly from the central portion of said disc 11 and is provided with one or more barbs 18. In applying the replacement eraser of FIG. 4 to a pencil having a worndown eraser the anchor member 17 is pressed into the stub of the worndown pencil eraser as far is possible and the barbs 18 prevent the replacement eraser from becoming loose on or detached from the pencil but these barbs can be manually torn loose from the eraser stub in which they are embedded if it is desired to use the replacement eraser on another pencil.

In the modified form of invention shown in FIG. 5 the eraser member 10 and mounting disc 11 are the same as those shown in FIGS. 1 to 4 and previously described but an anchor member 20 of different shape is provided. This anchor member 20, when viewed in elevation is of wavelike configuration. It is firmly secured to the disc 11 and protrudes from the side thereof opposite to the eraser member 10. This wavelike anchor member 20 can be pressed straight into a stub of a worndown pencil eraser and will hold firmly but is easier to withdraw from the stub in which it is embedded than a barbed anchor member is if the replacement eraser is to be used on another pencil.

In the modified form of the invention shown in FIG. 6 the eraser member 10' is the same as those shown in FIGS. 1 to 5 but the mounting disc 21 to which it is secured is of larger diameter than said eraser member and at least some of the peripheral portion 22 of said mounting disc 21 is bent upwardly and inwardly into clinched relationship with said eraser member 10. Said eraser member 10 can also be :adhesively secured to disc 21 if desired. The disc 21 is preferably large enough in size so that a barbed anchor member 23 can be struck or punched from it to be inserted into an eraser stub as hereinafter described.

Obviously two or more of the anchor members similar to those shown in FIGS. 4, 5 and 6 and which are adapted to be pressed straight into an eraser stub and be provided on a single disc similar to discs 10 or disc 21 if desired.

The foregoing description and accompanying drawings clearly disclose preferred embodiments of my invention but it will be understood that changes may be made within the scope of the following claims.

I claim:

1. A replacement eraser for use on :a lead pencil which has at one end a rigidly attached ferrule containing a stub of a worn-down eraser, said stub terminating substantially flush with the outer end of said ferrule, comprising a mounting disc of relatively strong material; :an eraser member secured to one side of said mounting disc; and an anchor member rigid with and protruding from the other side of said mounting disc, said anchor member being centrally positioned on said disc and being of relatively small cross sectional area and terminating in a pointed outer end and being capable of penetrating and being embedded in said eraser stub and when so embedded securing the replacement eraser to the pencil close to and in alignment with the eraser stub, said anchor member constituting the sole means for attaching the replacement eraser to the eraser stub and being shaped to resist withdrawal from said stub.

2. The replacement eraser as claimed in claim 1 in which at least one outwardly protruding tab is provided on the peripheral portion of said mounting disc, said tab retarding rolling of the replacement eraser and pencil to which it is attached. I

3. The replacement eraser as claimed in claim 1 in which the anchor member is provided with barbs shaped to resist withdrawal of said anchor member from an eraser stub in which it is embedded.

4. The replacement eraser as claimed in claim 1 in which the anchor member is of relatively small diameter and of helical shape, whereby it can be threaded into and out of engagement with an eraser stub of a pencil by rotation of the replacement eraser.

5. The replacement eraser as claimed in claim 1 in which the anchor member is substantially straight and substantially centrally positioned and perpendicular relative to said mounting disc, and in which barbs shaped to resist withdrawal of said anchor member from said eraser stub are provided on said anchor member.

6. The replacement eraser as claimed in claim 1 in which the anchor member, in elevation, is of wavelike configuration and capable of being thrust into an eraser stub in a pencil, the wavelike configuration of said anchor member providing increased resistance to withdrawalof said anchor member from the pencil stub.

7. The replacement eraser as claimed in claim 1 in which at least some of the marginal portion of the mounting disc is curved toward the eraser member and inwardly into securely clinched relationship with said eraser member.

References Cited UNITED STATES PATENTS 254,760 3/1332 Zeilin.

340,372 1/1907 Reckendorfer 15-10551 845,889 3/1907 Park 15-10553 1,104,514 7/1914 Kilstrom 15-429 1,534,440 4/1925 Carter 1642 2,658,480 11/1953 Hansen 15-429 3,343,668 9/1967 Politzer 401 s2 DANIEL BLUM, Primary Examiner 

